zbMATH — the first resource for mathematics

Examples
Geometry Search for the term Geometry in any field. Queries are case-independent.
Funct* Wildcard queries are specified by * (e.g. functions, functorial, etc.). Otherwise the search is exact.
"Topological group" Phrases (multi-words) should be set in "straight quotation marks".
au: Bourbaki & ti: Algebra Search for author and title. The and-operator & is default and can be omitted.
Chebyshev | Tschebyscheff The or-operator | allows to search for Chebyshev or Tschebyscheff.
"Quasi* map*" py: 1989 The resulting documents have publication year 1989.
so: Eur* J* Mat* Soc* cc: 14 Search for publications in a particular source with a Mathematics Subject Classification code (cc) in 14.
"Partial diff* eq*" ! elliptic The not-operator ! eliminates all results containing the word elliptic.
dt: b & au: Hilbert The document type is set to books; alternatively: j for journal articles, a for book articles.
py: 2000-2015 cc: (94A | 11T) Number ranges are accepted. Terms can be grouped within (parentheses).
la: chinese Find documents in a given language. ISO 639-1 language codes can also be used.

Operators
a & b logic and
a | b logic or
!ab logic not
abc* right wildcard
"ab c" phrase
(ab c) parentheses
Fields
any anywhere an internal document identifier
au author, editor ai internal author identifier
ti title la language
so source ab review, abstract
py publication year rv reviewer
cc MSC code ut uncontrolled term
dt document type (j: journal article; b: book; a: book article)
Implementation of chaotic secure communication systems based on OPA circuits. (English) Zbl 1068.94532
Summary: We propose a novel three-order autonomous circuit to construct a chaotic circuit with double scroll characteristic. The design idea is to use RLC elements and a nonlinear resistor. One of the salient features of the chaotic circuit is that the circuit has two flexible breakpoints of a nonlinear element, and the advantage of the flexible breakpoint is that it increases the complexity of the dynamical performance. Here, if we take a large and suitable breakpoint value, then the chaotic state can masking a large input signal in the circuit. Furthermore, we propose a secure communication hyperchaotic system based on the proposed chaotic circuits, where the chaotic communication system consists of a chaotic transmitter and a chaotic receiver. To achieve the synchronization between the transmitter and the receiver, we use a suitable Lyapunov function and the Lyapunov theorem to design the feedback control gain. Thus, the transmitting message masked by the chaotic state in the transmitter can be guaranteed to be perfectly recovered in the receiver. To achieve the system performance, some basic components containing OPA, resistor and capacitor elements are used to implement the proposed communication scheme. From the viewpoints of circuit implementation, this proposed chaotic circuit is superior to the Chua chaotic circuits. Finally, the test results, containing simulation and the circuit measurement, are shown to demonstrate that the proposed method is correct and feasible.
MSC:
94C05Analytic circuit theory
37D45Strange attractors, chaotic dynamics
94A05Communication theory